1. Field of the Invention
The present invention relates to high-voltage electrical component integration in electric vehicles, and in particular, to an integrated power electronic device for electric vehicles.
2. Description of Related Art
There are many high-voltage electrical components on an electric vehicle, such as a battery pack, a high-voltage cable distribution box, an electrical motor controller, an A/C compressor, a positive temperature coefficient (PTC) heater, a DC/DC converter, and an on-board charger. With the rapid but scattered developments of technologies for electric vehicle components, main core components such as the motor controller, the DC/DC converter, a vehicle controller, a battery management system, the high-voltage cable distribution box, and the on-board charger are designed and manufactured by different manufacturers, and are then integrated into a system in a main assembly plant. This practice has obvious advantages. For example, when different components need after-sales services, the manufacturers responsible for the different components may directly analyze and research the respective damaged components conveniently. However, there are also disadvantages as enumerated below.
First, when arranging many separate components in the front compartment of a vehicle, complex placements of various components are involved. Therefore, many mechanical holders are needed, and many snaps are required on the entire vehicle to fix wire harnesses from separate components. Moreover, each component has many complex high-voltage electrical connection lines. As such, the arrangement of the front compartment of the entire vehicle can be very unorganized and convoluted.
Second, processes for developing and verifying/certifying each component may be too cumbersome, adding significant cost and complexity to the system.
Therefore, many prior art integration approaches have emerged. For example, the motor controller, the DC/DC converter, the vehicle controller, the battery management system, the high-voltage cable distribution box, and the on-board charger may be integrated within an integrated box. This integration approach better resolves the problem of unorganized and convoluted arrangement of components in the front compartment. This integration, however, brings some other problems. For example, when a fault occurs to one component, the entire integrated box may need to be replaced, wasting significant resources.
For example, a schematic diagram of a prior art high-voltage cable distribution box is as shown in FIG. 1. Here, positive and negative buses coming from a power battery are connected to the high-voltage cable distribution box via a connector. In turn, these buses are connected, via a main fuse 15, to a main contactor 25 and branch relays 17 to various high-voltage components. Other connection lines are copper bus bars. Each branch is connected to various high-voltage components, such as a motor controller 18, a PTC heater (similar to a heater providing warm air within a passenger compartment of a traditional vehicle) 19, a compressor 20, an on-board fast-charging interface 21, an on-board charger 26, and a DC-DC converter 27.